In some technical applications data or signals have to be transmitted between different voltage domains, wherein each voltage domain has its own reference potential, and wherein these reference voltages may vary. An electronic circuit with two different voltage domains is, for example, an electronic circuit with a power transistor connected as a high-side switch, a drive circuit for the power transistor, and a control circuit. In this type of circuit, the control circuit generates a control signal which defines a desired switching state (on or off) of the power transistor and which is received by the drive circuit. The drive circuit generates a drive signal which is dependent on the control signal and which switches the power transistor on or off. The control signal is usually a voltage signal which is referenced to a fixed first reference potential, like ground. The drive signal, however, is usually referenced to a varying second reference potential. This second reference potential may correspond to a voltage across a load connected in series with the power transistor. The voltage swing of this second reference potential and, therefore, a voltage difference between the first and second reference potentials can be up to several hundred volts.
Due to this voltage difference, the control circuit and the drive circuit have to be galvanically decoupled. In other words: a signal transmission arrangement is required between the control circuit and the drive circuit, wherein this transmission arrangement is capable of blocking the high voltages that may occur between the control circuit and the drive circuit, and which enables a signal communication between the control circuit and the drive circuit. Besides optocouplers and level-shifters, transformers, in particular, coreless transformers, can be employed in signal transmission arrangements between two voltage domains.
A signal transmission arrangement with a transformer can be connected between any kind of sender circuit and any kind of receiver circuit. The signal transmission arrangement, besides the transformer, includes a sender circuit and a receiver circuit. The sender circuit is configured to generate a signal suitable to be transmitted via the transformer from user data provided by a signal source, and the receiver circuit is configured to retrieve the user data from the signal transmitted across the transformer. The basics of signal transmission via a signal transmission arrangement with a transformer are commonly known.
Like any electrical signal transmission method, electrical power is required for transmitting information via a signal transmission arrangement with a transformer. The power consumption of such a signal transmission arrangement can be dependent on a plurality of parameters, like the amplitude of signals applied to the transformer, the supply voltages of the sender and receiver circuits, a refresh rate, which is the rate at which transmitted data are again transmitted, a pulse width of pulses transmitted via the channel, etc. The power consumption can be reduced by suitably adjusting these parameters. However, a reduced power consumption may lead to an increased error rate.
There is, therefore, a need to provide a signal transmission arrangement which provides for a safe signal transmission at a low power consumption, and to provide a corresponding signal transmission method.